The present invention relates to a facsimile apparatus for transmitting/receiving a remote command and transferring character files and data files.
Conventionally, as an operation other than a normal transmission/reception operation in a facsimile apparatus, for example, when remote commands are transmitted/received, they are transmitted upon being divided in units of fixed packet lengths or in units of packets in correspondence with the remote commands.
However, in such a facsimile apparatus, since remote commands in a file memory are divided in units of fixed lengths regardless of their contents, a response to a specific remote command in a file from a receiving facsimile apparatus cannot be expected. For this reason, when remote commands are terminated as an error during transmission, the remote command transmission must be restarted from the beginning.
A conventional facsimile apparatus discriminates the presence/absence of a transmission original in its communication protocol. When an original is present, a communication control program is started to transmit a original content to an apparatus on the other end of the line. In an apparatus using the ECM procedure of the CCITT recommendation T.30 in its communication protocol, only image information is transmitted as facsimile information.
However, in a facsimile apparatus of this type, a character file cannot be transmitted in a transmission function other than an original transmission function due to a limitation on the communication protocol. When the ECM procedure of the CCITT recommendation T.30 is used, a data file cannot be transmitted.
A conventional facsimile apparatus has many registration items such as abbreviated dial numbers, a user telephone number, a user abbreviation, and the like. For this reason, when the apparatus is installed, a service person must manually perform input operations of these items for a long period of time.
When a trouble of an apparatus occurs, a service person must go to the installation site of the apparatus to make adjustments of the apparatus.
In order to reduce time/economic losses caused when a service person goes to the site of installation, a technique for registering data of a facsimile apparatus or adjusting the apparatus from a remote place by utilizing a communication function of the facsimile apparatus has been proposed.
When data registration is performed from a remote place, it is easiest to perform communications in an HDLC frame format used by the facsimile apparatus in a communication procedure using a 300-bps modem, following the CCITT recommendation V.21, of the facsimile apparatus so as to read/write data from/in an internal memory of the apparatus.
In the CCITT recommendation T.30 which defines the standards of the facsimile apparatus, however, a preamble for a 300-bps binary code signal is defined as a series of flag sequences of 1 second+15% (CCITT T.30 5.3.1.1), and the maximum length of one frame is defined to be 3 seconds +15%. For this reason, an insignificant preamble of 1 second must be added to significant data of 3 seconds, thus providing disadvantages in data communication efficiency.
The above-mentioned standards are determined assuming a frame having a maximum length of about 100 bytes. For this reason, to receive data exceeding 3 seconds without limitations requires a considerable change in software. When reception of infinitely large data is permitted, even when a communication error occurs, an error portion cannot immediately re-sent, and all the data must be re-sent after transmission for a long period of time, thus considerably increasing the communication time.
Furthermore, the above-mentioned time period of 1 second is determined as a countermeasure against a factor such as an echo occurring on a communication line. It is not desirable to merely shorten this time period since a communication error may often occur due to a factor such as an echo in a long-distance communication mode.
In the remote registration operation, a receiver must inform to a transmitter whether or not registration is normally performed after the receiver executes received commands. However, the registration items of the facsimile apparatus are as many as several tens to several hundreds of items. For this reason, if registration is executed for each item, and a response for this registration is sent back, communications require a very long period time.
In order to eliminate the above-mentioned drawback, a method of simultaneously executing registrations after all the commands are received, and then sending back a result indicating whether or not the registrations are normally performed is also known. In this case, however, in order to receive all the commands, a large-capacity memory is required. In addition, when the registrations cannot be performed, and the receiver sends back a negative response, the transmitter cannot identify which of items cannot be registered.
When data registrations are performed from a remote place, a host apparatus for performing the registration operation must recognize the data format in the receiver, and must perform a write access matching with the recognized format. If this is not done, normal registrations cannot be performed in the receiver, thus causing a trouble.
For example, if the user tries to register a 30-digit telephone number to a registration area for abbreviated dial numbers of a facsimile apparatus which can store a maximum 20-digit abbreviated dial number, that is, if the number of digits of the telephone number to be registered exceeds the registration area, dial numbers stored in an area adjacent to the above registration area may be possibly damaged. However, the registration items of the facsimile apparatus are as many as several tens to several hundreds of items. For this reason, if registration is executed for each item, and a response for this registration is sent back, communications require a very long period time.
When remote registrations are to be performed, an operator is encountered to bear this in mind, and is expected to make operations after he or she recognizes the type of receiving apparatus. However, if the operator recognizes a wrong type of receiving apparatus, the content of the RAM may be destroyed.
Furthermore, even in apparatuses of the same type, data attributes and RAM storage addresses may be changed depending on destination places, program versions, and the presence/absence of optional functions. However, since these pieces of information cannot be normally discriminated by a user, a service person must consequently go to the installation site, thus disabling the remote registrations.